if i take my pot with newly rooted hibiscus in them and put them in a bigger container made of foamed polyurithane(staying in there original pot)and fill the sides with soil.and put the container in our shelter.is it good for winter cold protection?
1.the shelter will not be warmer than the patio but there will be no wind 'rain 'snow only dim light and air.
2.i thought the plants roots need warmth and maybe the top will suffer and die off but hoping the spring will start everything again from the begining.
3.i thought the warmth will come fromA.the soil around the pot B.polyurithane is warm and i used these foams to protect the bases of plants on our outdoor patios.in winter.they are good isolaters.
4.why put them in the shelter?i went wild this summer and have to think of relocation of many plants that may suffer in winter here.our indoors are not big enough.i may have to give some away as gifts....
i have rooted4 beleprones.........4 plumerias 20 hoyas 5 peperomias......and others.
5.if i do do this whole thing should it be close to real winter....so the process will be gradual or let the plants enjoy natural environment untill it gets rough?

How cold does it get, at worst in your winter, David? No matter how much you insulate the plants, if they are up out of the ground (which retains a lot of heat) they will eventually get down to the lowest temperature of the ambient air unless you supply a heat source. Just like the ice will always melt eventually, no matter how well insulated a cooler is.

Things like hibiscus will not tolerate having their roots get too cold. You'd be better - and further ahead next spring - to take cuttings and bring them indoors for the winter.

Btw, there is a whole forum on Tropicals and a great thread about "Growing Tropicals in the North" where there are a lot of people who do what we call "pushing the zone". Which is what you are doing - growing plants that are too tender for your climate zone. The thread "Growing tropicals in the north" in Tropicals forum

You need to branch out and make use of the specific threads for your plants! You will have contact with many more people on ATP that way.

great idea thankyou